HPV Vaccine Demonstrates Sustained Protection

WEDNESDAY, July 21 (HealthDay News) -- The quadrivalent human papillomavirus (HPV) vaccine appears to provide strong and sustained protection against low-grade lesions attributable to HPV, according to research published July 20 in BMJ.

Joakim Dillner, M.D., of Lund University in Sweden, and colleagues examined data from two trials of 17,622 women, aged 16 to 26 years, randomized to three doses of quadrivalent HPV vaccine for serotypes 6, 11, 16, and 18 or placebo to gauge the efficacy of the vaccine in preventing low-grade cervical, vulvar, and vaginal intraepithelial neoplasias and condyloma acuminata (genital warts). The final results reported were from 42 months of follow-up.

The researchers found the vaccine to be 96 and 100 percent protective against grade I cervical intraepithelial neoplasia and grade I vulvar and vaginal intraepithelial neoplasia, respectively, and 99 percent effective against condyloma. The vaccine also proved highly effective in reducing any lesion regardless of HPV type, with an efficacy of 30 percent for cervical neoplasia, 75 percent for vulvar neoplasia, 48 percent for vaginal neoplasia, and 83 percent for condyloma.

"Quadrivalent HPV vaccine provided sustained protection against low-grade lesions attributable to vaccine HPV types (6, 11, 16, and 18) and a substantial reduction in the burden of these diseases through 42 months of follow-up," the authors write.

The studies were funded by Merck Research Laboratories. Several authors disclosed financial ties to pharmaceutical companies, including Merck.